The Bronx

Cops on Saturday released a photo of a man who allegedly stabbed a straphanger on a 2 train in the South Bronx.

William Quinones, 39, repeatedly stabbed the victim in the torso on
Dec. 20 just before 2 p.m. after getting off a Brooklyn-bound 2 train at the East 149th Street/Third Avenue station, said law-enforcement authorities.

Cops describe Quinones as 5-foot-10 and 185 pounds with brown eyes and black hair that he is known to wear in braids.

The victim was rushed to Lincoln Hospital in stable condition.

One man is fighting for his life and two other people are recovering after a gunman opened fire on a Tremont street early Saturday, cops said.

The gunman pulled a pistol and blasted an unidentified man in the chest at LaFontaine Avenue and East 179th Street at around 2 a.m., according to police.

Then he pointed the gun at a 35-year-old man and shot him in the leg, cops said.

Both victims were rushed to St. Barnabas Hospital.

One unidentified victim is in critical condition, and the 35-year old was in ­stable condition.

An 18-year-old woman shot in the thigh in the melee is expected to survive, said law-enforcement authorities.

Two robbers took a man’s backpack containing more than $2,000 in cash, tools and electronics in University Heights Thursday night, police said.

The 38-year-old victim was standing in front of 2407 Grand Concourse at 11:20 p.m. when the two suspects ripped the backpack from his body, cops said.

Police describe one suspect as a man in his late teens, 5-foot-9 and sporting an afro haircut.

The second suspect is in his late teens, 5-foot-7 with braided hair, said authorities.

Brooklyn

A man exposed himself while grabbing and groping a woman in East New York last Tuesday, cops said.

The suspect was following the 63-year-old woman near Grant and Atlantic avenues at about 8:25 a.m. on Aug. 5 when he began sexually menacing the woman.

Cops describe the man as age 20 to 25 and weighing 140 to 150 pounds.

Police have arrested a man in connection with a Greepoint subway assault.

Cops say Jasner Jimenez, 24, of Brooklyn, got into a fight with a 54-year-old woman on a Manhattan-bound L train on July 26.

Jimenez followed her as she and her child tried to walk away from him, according to cops.

Police say Jimenez then caught up with the woman and smashed her head into a metal pole.